Health Effects of Artificial Light

6. How and where are people exposed to artificial light?

Exposure to UV from artificial light is equivalent to one
week vacation in a sunny destination

There is very little information on personal exposures to
different indoor lights but it is possible to make estimates by
choosing exposure situations where there is some potential risk,
either because the eye or the skin are exposed to UV from the
general ambient light, or because of direct exposure of the eye
to the blue component of light.

Office workers and school children are exposed to some UV and
blue light from fluorescent
lamps and task-lamps, for up to 8 hours a day. Those
working in factories or large stores are exposed throughout the
working day to more intense light sources but these are placed
relatively far away in high ceilings. Customers visiting these
shops are similarly exposed, but for much shorter periods of
time. Performers and presenters on TV studios are under very
bright lights so are exposed to UV, blue light and glare. Night
drivers are also exposed to glare from headlights but only for a
very short time so the main risk is that glare could cause them
to have an accident rather than any eye or skin conditions.
Finally, night reading for one or two hours using CFLs, LEDs or
incandescent lights would expose people to some blue
light.

People exposed to indoor lights receive some UV radiation
which accumulates over a person’s lifetime and contributes to
the risk of developing skin
cancer. Exposure to fluorescent light in the home is
generally negligible compared to that at school and the
workplace. Therefore, worst-case scenarios consider lifetime
exposure in school of 6 hours a day for 40 school weeks a year
from 5 to 20 years of age, and 8 hours a week at work from 20 to
65 years of age and for 48 weeks a year.

Exposure and consequent risk depend very strongly on the lamp
used. As a comparison, the added annual risk from a lamp at the
very top limit of what is classed as safe is equivalent to 1
week of holiday in the Mediterranean and about 100 times smaller
than living in Australia. At the other extreme, lamps emitting
low levels of UV pose almost no added risk.

In practice, exposure to fluorescent lamps is much lower than the
worst-case scenarios considered here and more data on personal
exposures is needed to improve these estimates.
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